YouTuber Blown Away by Insane Sleeper S550 GT

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Looks like your standard Mustang GT, but it packs 800 hp under the hood with an On 3 turbo kit that even makes ThatDudeInBlue blush.

If done right, Mustangs have always been a source for cheap speed. But there were always, ahem, caveats. There was some wheezy six- or four-cylinder boat anchor at the bottom of the food chain. In the S550 cars, cheap speed comes standard. The base EcoBoost car makes 310 horsepower – more than a V8 powered car did 20 years ago. And today’s GT? We’re talking 460 horses for $35,000. Simply put, that’s insane.

And that’s what this video is all about. Posted by YouTuber ThatDudeInBlue, David is behind the wheel of what he calls “the most sleeper-ist S550 I’ve ever seen.” At first glance, it looks like your standard S550 GT. But under the hood, it has an On 3 turbo kit. Right away, he addresses the kit’s reputation for being “cheap.” Nonetheless, he’s completely won over by the amount of power it has.

Twin-turbocharged "sleeper" S550 Mustang GT.

As a testament to how stout the S550 is, the car is still riding on its stock tires and suspension. The added power is no problem here. “You see the tiny little intercooler up front. But at the same time, he has an EcoBoost grille up front to troll everyone, which is magnificent,” David says. With that “cheap” On 3 kit, this GT now makes an insane 813 wheel horsepower.

And that’s it. As David explains: “Stock motor. No oil pump gears. Through the auto [transmission].” It says something that the Ford mechanicals are robust enough to handle all this power. He then makes the bold claim that the 6R80 automatic transmission is the better choice for the Coyote V8. While we aren’t sure about that, the fact that people can put this much power through one without blowing it up is pretty impressive.

Unfortunately, those stock tires aren’t really up to hold down all that power. “This is like driving on ice,” David says. “I am fighting this thing to keep it straight.” He later says: “If this thing had a tire on it and it just hooked and went, I can’t imagine how fast it would be.”

Twin-turbocharged "sleeper" S550 Mustang GT.

Still, the whine of the turbos and the grunt of the Mustang GT V8 sound absolutely intoxicating. He talks about the number of insane mods people have done to otherwise stock Coyote motors. “That’s why I always joke about the Coyote being a cheating motor. Compared to other platforms, it’s so much easier to go fast.”

So the Mustang GT is a sleeper, it comes with a ton of horsepower on tap, and it can be modded to high heaven on stock mechanicals. Is it the perfect car? We can’t say. But it is seriously close. “This car is just so dumb fast for the budget,” David says, “that it’s just incredible to me.” It’s pretty incredible to all of us.

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James Derek Sapienza has worked as a writer and editor in the world of automotive journalism since 2015.

He has a BS in History at SUNY Brockport, with a focus on American popular culture. A fan of the classics with a special interest in German cars, he is a proud owner of a 1991 W124 Mercedes. He is a frequent contributor to Mustang Forums, MBWorld, 5Series, Rennlist, and more.

James can be reached at [email protected]

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